I think you might be talking about "fraudulent transaction/cardholder does not recognize" disputes. Yes, when using 3DS (which is now much more common at least in Europe, due to often being required by regulation in the EU/EEA), these are much less likely to be won by the issuer.
But "merchant does not let me cancel" isn't a fraud dispute (and in fact would probably be lost by the issuing bank if raised as such). Those "non-fraudulent disagreement with the merchant disputes" work very similarly in the US and in Europe.
No, you're just wrong here. Merchant doesn't let me cancel will almost always be won by the vendor when they demonstrate that they do allow cancellations within the bounds of the law and contracts. I've won many of these in the EU, too (we actually never lost a dispute for non-compliance with card network rules, because we were _very_ compliant).
I can only assume you are from the US and are assuming your experience will generalise, but it simply does not. Like night and day. Most EU residents who try using chargebacks for illegitimate dispute resolution learn these lessons quickly, as there are far more card cancellations for "friendly fraud" than merchant account closures for excessive chargebacks in the EU - the polar opposite of the US.
And have you won one of these cases in a scenario where the merchant website has a blanket IP ban? That seems very different from cardholders incapable of clicking an “unsubscribe” button they have access to.
But "merchant does not let me cancel" isn't a fraud dispute (and in fact would probably be lost by the issuing bank if raised as such). Those "non-fraudulent disagreement with the merchant disputes" work very similarly in the US and in Europe.